916 lines
26 KiB
C
916 lines
26 KiB
C
/****************************************************************************
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THIS SOFTWARE IS NOT COPYRIGHTED
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HP offers the following for use in the public domain. HP makes no
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warranty with regard to the software or it's performance and the
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user accepts the software "AS IS" with all faults.
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HP DISCLAIMS ANY WARRANTIES, EXPRESS OR IMPLIED, WITH REGARD
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TO THIS SOFTWARE INCLUDING BUT NOT LIMITED TO THE WARRANTIES
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OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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****************************************************************************/
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/****************************************************************************
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* Header: remcom.c,v 1.34 91/03/09 12:29:49 glenne Exp $
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*
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* Module name: remcom.c $
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* Revision: 1.34 $
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* Date: 91/03/09 12:29:49 $
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* Contributor: Lake Stevens Instrument Division$
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*
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* Description: low level support for gdb debugger. $
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*
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* Considerations: only works on target hardware $
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*
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* Written by: Glenn Engel $
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* ModuleState: Experimental $
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*
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* NOTES: See Below $
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*
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* Modified for 386 by Jim Kingdon, Cygnus Support.
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*
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* To enable debugger support, two things need to happen. One, a
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* call to set_debug_traps() is necessary in order to allow any breakpoints
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* or error conditions to be properly intercepted and reported to gdb.
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* Two, a breakpoint needs to be generated to begin communication. This
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* is most easily accomplished by a call to breakpoint(). Breakpoint()
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* simulates a breakpoint by executing a trap #1.
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*
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* The external function exceptionHandler() is
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* used to attach a specific handler to a specific 386 vector number.
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* It should use the same privilege level it runs at. It should
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* install it as an interrupt gate so that interrupts are masked
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* while the handler runs.
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* Also, need to assign exceptionHook and oldExceptionHook.
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*
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* Because gdb will sometimes write to the stack area to execute function
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* calls, this program cannot rely on using the supervisor stack so it
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* uses it's own stack area reserved in the int array remcomStack.
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*
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*************
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*
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* The following gdb commands are supported:
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*
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* command function Return value
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*
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* g return the value of the CPU registers hex data or ENN
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* G set the value of the CPU registers OK or ENN
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*
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* mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN
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* MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN
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*
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* c Resume at current address SNN ( signal NN)
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* cAA..AA Continue at address AA..AA SNN
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*
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* s Step one instruction SNN
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* sAA..AA Step one instruction from AA..AA SNN
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*
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* k kill
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*
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* ? What was the last sigval ? SNN (signal NN)
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*
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* All commands and responses are sent with a packet which includes a
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* checksum. A packet consists of
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*
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* $<packet info>#<checksum>.
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*
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* where
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* <packet info> :: <characters representing the command or response>
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* <checksum> :: < two hex digits computed as modulo 256 sum of <packetinfo>>
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*
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* When a packet is received, it is first acknowledged with either '+' or '-'.
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* '+' indicates a successful transfer. '-' indicates a failed transfer.
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*
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* Example:
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*
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* Host: Reply:
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* $m0,10#2a +$00010203040506070809101112131415#42
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*
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****************************************************************************/
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#include <stdio.h>
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#include <string.h>
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/************************************************************************
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*
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* external low-level support routines
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*/
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typedef void (*ExceptionHook)(int); /* pointer to function with int parm */
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typedef void (*Function)(); /* pointer to a function */
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extern putDebugChar(); /* write a single character */
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extern getDebugChar(); /* read and return a single char */
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extern Function exceptionHandler(); /* assign an exception handler */
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extern ExceptionHook exceptionHook; /* hook variable for errors/exceptions */
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/************************************************************************/
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/* BUFMAX defines the maximum number of characters in inbound/outbound buffers*/
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/* at least NUMREGBYTES*2 are needed for register packets */
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#define BUFMAX 400
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static char initialized; /* boolean flag. != 0 means we've been initialized */
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int remote_debug;
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/* debug > 0 prints ill-formed commands in valid packets & checksum errors */
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void waitabit();
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static const char hexchars[]="0123456789abcdef";
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/* Number of bytes of registers. */
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#define NUMREGBYTES 64
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enum regnames {EAX, ECX, EDX, EBX, ESP, EBP, ESI, EDI,
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PC /* also known as eip */,
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PS /* also known as eflags */,
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CS, SS, DS, ES, FS, GS};
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/*
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* these should not be static cuz they can be used outside this module
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*/
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int registers[NUMREGBYTES/4];
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#define STACKSIZE 10000
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int remcomStack[STACKSIZE/sizeof(int)];
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static int* stackPtr = &remcomStack[STACKSIZE/sizeof(int) - 1];
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/*
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* In many cases, the system will want to continue exception processing
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* when a continue command is given.
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* oldExceptionHook is a function to invoke in this case.
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*/
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static ExceptionHook oldExceptionHook;
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/*************************** ASSEMBLY CODE MACROS *************************/
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/* */
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extern void
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return_to_prog ();
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/* Restore the program's registers (including the stack pointer, which
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means we get the right stack and don't have to worry about popping our
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return address and any stack frames and so on) and return. */
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asm(".text");
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asm(".globl _return_to_prog");
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asm("_return_to_prog:");
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asm(" movw _registers+44, %ss");
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asm(" movl _registers+16, %esp");
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asm(" movl _registers+4, %ecx");
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asm(" movl _registers+8, %edx");
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asm(" movl _registers+12, %ebx");
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asm(" movl _registers+20, %ebp");
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asm(" movl _registers+24, %esi");
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asm(" movl _registers+28, %edi");
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asm(" movw _registers+48, %ds");
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asm(" movw _registers+52, %es");
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asm(" movw _registers+56, %fs");
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asm(" movw _registers+60, %gs");
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asm(" movl _registers+36, %eax");
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asm(" pushl %eax"); /* saved eflags */
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asm(" movl _registers+40, %eax");
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asm(" pushl %eax"); /* saved cs */
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asm(" movl _registers+32, %eax");
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asm(" pushl %eax"); /* saved eip */
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asm(" movl _registers, %eax");
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/* use iret to restore pc and flags together so
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that trace flag works right. */
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asm(" iret");
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#define BREAKPOINT() asm(" int $3");
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/* Put the error code here just in case the user cares. */
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int gdb_i386errcode;
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/* Likewise, the vector number here (since GDB only gets the signal
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number through the usual means, and that's not very specific). */
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int gdb_i386vector = -1;
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/* GDB stores segment registers in 32-bit words (that's just the way
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m-i386v.h is written). So zero the appropriate areas in registers. */
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#define SAVE_REGISTERS1() \
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asm ("movl %eax, _registers"); \
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asm ("movl %ecx, _registers+4"); \
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asm ("movl %edx, _registers+8"); \
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asm ("movl %ebx, _registers+12"); \
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asm ("movl %ebp, _registers+20"); \
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asm ("movl %esi, _registers+24"); \
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asm ("movl %edi, _registers+28"); \
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asm ("movw $0, %ax"); \
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asm ("movw %ds, _registers+48"); \
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asm ("movw %ax, _registers+50"); \
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asm ("movw %es, _registers+52"); \
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asm ("movw %ax, _registers+54"); \
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asm ("movw %fs, _registers+56"); \
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asm ("movw %ax, _registers+58"); \
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asm ("movw %gs, _registers+60"); \
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asm ("movw %ax, _registers+62");
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#define SAVE_ERRCODE() \
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asm ("popl %ebx"); \
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asm ("movl %ebx, _gdb_i386errcode");
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#define SAVE_REGISTERS2() \
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asm ("popl %ebx"); /* old eip */ \
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asm ("movl %ebx, _registers+32"); \
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asm ("popl %ebx"); /* old cs */ \
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asm ("movl %ebx, _registers+40"); \
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asm ("movw %ax, _registers+42"); \
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asm ("popl %ebx"); /* old eflags */ \
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asm ("movl %ebx, _registers+36"); \
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/* Now that we've done the pops, we can save the stack pointer."); */ \
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asm ("movw %ss, _registers+44"); \
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asm ("movw %ax, _registers+46"); \
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asm ("movl %esp, _registers+16");
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/* See if mem_fault_routine is set, if so just IRET to that address. */
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#define CHECK_FAULT() \
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asm ("cmpl $0, _mem_fault_routine"); \
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asm ("jne mem_fault");
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asm (".text");
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asm ("mem_fault:");
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/* OK to clobber temp registers; we're just going to end up in set_mem_err. */
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/* Pop error code from the stack and save it. */
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asm (" popl %eax");
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asm (" movl %eax, _gdb_i386errcode");
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asm (" popl %eax"); /* eip */
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/* We don't want to return there, we want to return to the function
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pointed to by mem_fault_routine instead. */
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asm (" movl _mem_fault_routine, %eax");
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asm (" popl %ecx"); /* cs (low 16 bits; junk in hi 16 bits). */
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asm (" popl %edx"); /* eflags */
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/* Remove this stack frame; when we do the iret, we will be going to
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the start of a function, so we want the stack to look just like it
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would after a "call" instruction. */
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asm (" leave");
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/* Push the stuff that iret wants. */
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asm (" pushl %edx"); /* eflags */
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asm (" pushl %ecx"); /* cs */
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asm (" pushl %eax"); /* eip */
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/* Zero mem_fault_routine. */
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asm (" movl $0, %eax");
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asm (" movl %eax, _mem_fault_routine");
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asm ("iret");
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#define CALL_HOOK() asm("call _remcomHandler");
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/* This function is called when a i386 exception occurs. It saves
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* all the cpu regs in the _registers array, munges the stack a bit,
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* and invokes an exception handler (remcom_handler).
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*
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* stack on entry: stack on exit:
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* old eflags vector number
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* old cs (zero-filled to 32 bits)
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* old eip
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*
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*/
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extern void _catchException3();
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asm(".text");
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asm(".globl __catchException3");
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asm("__catchException3:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $3");
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CALL_HOOK();
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/* Same thing for exception 1. */
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extern void _catchException1();
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asm(".text");
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asm(".globl __catchException1");
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asm("__catchException1:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $1");
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CALL_HOOK();
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/* Same thing for exception 0. */
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extern void _catchException0();
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asm(".text");
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asm(".globl __catchException0");
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asm("__catchException0:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $0");
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CALL_HOOK();
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/* Same thing for exception 4. */
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extern void _catchException4();
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asm(".text");
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asm(".globl __catchException4");
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asm("__catchException4:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $4");
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CALL_HOOK();
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/* Same thing for exception 5. */
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extern void _catchException5();
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asm(".text");
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asm(".globl __catchException5");
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asm("__catchException5:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $5");
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CALL_HOOK();
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/* Same thing for exception 6. */
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extern void _catchException6();
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asm(".text");
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asm(".globl __catchException6");
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asm("__catchException6:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $6");
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CALL_HOOK();
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/* Same thing for exception 7. */
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extern void _catchException7();
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asm(".text");
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asm(".globl __catchException7");
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asm("__catchException7:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $7");
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CALL_HOOK();
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/* Same thing for exception 8. */
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extern void _catchException8();
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asm(".text");
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asm(".globl __catchException8");
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asm("__catchException8:");
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SAVE_REGISTERS1();
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SAVE_ERRCODE();
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SAVE_REGISTERS2();
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asm ("pushl $8");
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CALL_HOOK();
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/* Same thing for exception 9. */
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extern void _catchException9();
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asm(".text");
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asm(".globl __catchException9");
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asm("__catchException9:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $9");
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CALL_HOOK();
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/* Same thing for exception 10. */
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extern void _catchException10();
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asm(".text");
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asm(".globl __catchException10");
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asm("__catchException10:");
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SAVE_REGISTERS1();
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SAVE_ERRCODE();
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SAVE_REGISTERS2();
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asm ("pushl $10");
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CALL_HOOK();
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/* Same thing for exception 12. */
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extern void _catchException12();
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asm(".text");
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asm(".globl __catchException12");
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asm("__catchException12:");
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SAVE_REGISTERS1();
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SAVE_ERRCODE();
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SAVE_REGISTERS2();
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asm ("pushl $12");
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CALL_HOOK();
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/* Same thing for exception 16. */
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extern void _catchException16();
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asm(".text");
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asm(".globl __catchException16");
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asm("__catchException16:");
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SAVE_REGISTERS1();
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SAVE_REGISTERS2();
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asm ("pushl $16");
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CALL_HOOK();
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/* For 13, 11, and 14 we have to deal with the CHECK_FAULT stuff. */
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/* Same thing for exception 13. */
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extern void _catchException13 ();
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asm (".text");
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asm (".globl __catchException13");
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asm ("__catchException13:");
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CHECK_FAULT();
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SAVE_REGISTERS1();
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SAVE_ERRCODE();
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SAVE_REGISTERS2();
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asm ("pushl $13");
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CALL_HOOK();
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/* Same thing for exception 11. */
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extern void _catchException11 ();
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asm (".text");
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asm (".globl __catchException11");
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asm ("__catchException11:");
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CHECK_FAULT();
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SAVE_REGISTERS1();
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SAVE_ERRCODE();
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SAVE_REGISTERS2();
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asm ("pushl $11");
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CALL_HOOK();
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/* Same thing for exception 14. */
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extern void _catchException14 ();
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asm (".text");
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asm (".globl __catchException14");
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asm ("__catchException14:");
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CHECK_FAULT();
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SAVE_REGISTERS1();
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SAVE_ERRCODE();
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SAVE_REGISTERS2();
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asm ("pushl $14");
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CALL_HOOK();
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/*
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* remcomHandler is a front end for handle_exception. It moves the
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* stack pointer into an area reserved for debugger use.
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*/
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asm("_remcomHandler:");
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asm(" popl %eax"); /* pop off return address */
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asm(" popl %eax"); /* get the exception number */
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asm(" movl _stackPtr, %esp"); /* move to remcom stack area */
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asm(" pushl %eax"); /* push exception onto stack */
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asm(" call _handle_exception"); /* this never returns */
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void _returnFromException()
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{
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return_to_prog ();
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}
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int hex(ch)
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char ch;
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{
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if ((ch >= 'a') && (ch <= 'f')) return (ch-'a'+10);
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if ((ch >= '0') && (ch <= '9')) return (ch-'0');
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if ((ch >= 'A') && (ch <= 'F')) return (ch-'A'+10);
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return (-1);
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}
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/* scan for the sequence $<data>#<checksum> */
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void getpacket(buffer)
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char * buffer;
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{
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unsigned char checksum;
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unsigned char xmitcsum;
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int i;
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int count;
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char ch;
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do {
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/* wait around for the start character, ignore all other characters */
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while ((ch = (getDebugChar() & 0x7f)) != '$');
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checksum = 0;
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xmitcsum = -1;
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count = 0;
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/* now, read until a # or end of buffer is found */
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while (count < BUFMAX) {
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ch = getDebugChar() & 0x7f;
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if (ch == '#') break;
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checksum = checksum + ch;
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buffer[count] = ch;
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count = count + 1;
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}
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buffer[count] = 0;
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if (ch == '#') {
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xmitcsum = hex(getDebugChar() & 0x7f) << 4;
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xmitcsum += hex(getDebugChar() & 0x7f);
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if ((remote_debug ) && (checksum != xmitcsum)) {
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fprintf (stderr ,"bad checksum. My count = 0x%x, sent=0x%x. buf=%s\n",
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checksum,xmitcsum,buffer);
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}
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if (checksum != xmitcsum) putDebugChar('-'); /* failed checksum */
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else {
|
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putDebugChar('+'); /* successful transfer */
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/* if a sequence char is present, reply the sequence ID */
|
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if (buffer[2] == ':') {
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putDebugChar( buffer[0] );
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putDebugChar( buffer[1] );
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/* remove sequence chars from buffer */
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count = strlen(buffer);
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for (i=3; i <= count; i++) buffer[i-3] = buffer[i];
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}
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}
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}
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} while (checksum != xmitcsum);
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}
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|
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/* send the packet in buffer. */
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void putpacket(buffer)
|
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char * buffer;
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{
|
|
unsigned char checksum;
|
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int count;
|
|
char ch;
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|
|
/* $<packet info>#<checksum>. */
|
|
do {
|
|
putDebugChar('$');
|
|
checksum = 0;
|
|
count = 0;
|
|
|
|
while (ch=buffer[count]) {
|
|
if (! putDebugChar(ch)) return;
|
|
checksum += ch;
|
|
count += 1;
|
|
}
|
|
|
|
putDebugChar('#');
|
|
putDebugChar(hexchars[checksum >> 4]);
|
|
putDebugChar(hexchars[checksum % 16]);
|
|
|
|
} while ((getDebugChar() & 0x7f) != '+');
|
|
|
|
}
|
|
|
|
char remcomInBuffer[BUFMAX];
|
|
char remcomOutBuffer[BUFMAX];
|
|
static short error;
|
|
|
|
|
|
void debug_error(format, parm)
|
|
char * format;
|
|
char * parm;
|
|
{
|
|
if (remote_debug) fprintf (stderr,format,parm);
|
|
}
|
|
|
|
/* Address of a routine to RTE to if we get a memory fault. */
|
|
static void (*volatile mem_fault_routine)() = NULL;
|
|
|
|
/* Indicate to caller of mem2hex or hex2mem that there has been an
|
|
error. */
|
|
static volatile int mem_err = 0;
|
|
|
|
void
|
|
set_mem_err ()
|
|
{
|
|
mem_err = 1;
|
|
}
|
|
|
|
/* These are separate functions so that they are so short and sweet
|
|
that the compiler won't save any registers (if there is a fault
|
|
to mem_fault, they won't get restored, so there better not be any
|
|
saved). */
|
|
int
|
|
get_char (addr)
|
|
char *addr;
|
|
{
|
|
return *addr;
|
|
}
|
|
|
|
void
|
|
set_char (addr, val)
|
|
char *addr;
|
|
int val;
|
|
{
|
|
*addr = val;
|
|
}
|
|
|
|
/* convert the memory pointed to by mem into hex, placing result in buf */
|
|
/* return a pointer to the last char put in buf (null) */
|
|
/* If MAY_FAULT is non-zero, then we should set mem_err in response to
|
|
a fault; if zero treat a fault like any other fault in the stub. */
|
|
char* mem2hex(mem, buf, count, may_fault)
|
|
char* mem;
|
|
char* buf;
|
|
int count;
|
|
int may_fault;
|
|
{
|
|
int i;
|
|
unsigned char ch;
|
|
|
|
if (may_fault)
|
|
mem_fault_routine = set_mem_err;
|
|
for (i=0;i<count;i++) {
|
|
ch = get_char (mem++);
|
|
if (may_fault && mem_err)
|
|
return (buf);
|
|
*buf++ = hexchars[ch >> 4];
|
|
*buf++ = hexchars[ch % 16];
|
|
}
|
|
*buf = 0;
|
|
if (may_fault)
|
|
mem_fault_routine = NULL;
|
|
return(buf);
|
|
}
|
|
|
|
/* convert the hex array pointed to by buf into binary to be placed in mem */
|
|
/* return a pointer to the character AFTER the last byte written */
|
|
char* hex2mem(buf, mem, count, may_fault)
|
|
char* buf;
|
|
char* mem;
|
|
int count;
|
|
int may_fault;
|
|
{
|
|
int i;
|
|
unsigned char ch;
|
|
|
|
if (may_fault)
|
|
mem_fault_routine = set_mem_err;
|
|
for (i=0;i<count;i++) {
|
|
ch = hex(*buf++) << 4;
|
|
ch = ch + hex(*buf++);
|
|
set_char (mem++, ch);
|
|
if (may_fault && mem_err)
|
|
return (mem);
|
|
}
|
|
if (may_fault)
|
|
mem_fault_routine = NULL;
|
|
return(mem);
|
|
}
|
|
|
|
/* this function takes the 386 exception vector and attempts to
|
|
translate this number into a unix compatible signal value */
|
|
int computeSignal( exceptionVector )
|
|
int exceptionVector;
|
|
{
|
|
int sigval;
|
|
switch (exceptionVector) {
|
|
case 0 : sigval = 8; break; /* divide by zero */
|
|
case 1 : sigval = 5; break; /* debug exception */
|
|
case 3 : sigval = 5; break; /* breakpoint */
|
|
case 4 : sigval = 16; break; /* into instruction (overflow) */
|
|
case 5 : sigval = 16; break; /* bound instruction */
|
|
case 6 : sigval = 4; break; /* Invalid opcode */
|
|
case 7 : sigval = 8; break; /* coprocessor not available */
|
|
case 8 : sigval = 7; break; /* double fault */
|
|
case 9 : sigval = 11; break; /* coprocessor segment overrun */
|
|
case 10 : sigval = 11; break; /* Invalid TSS */
|
|
case 11 : sigval = 11; break; /* Segment not present */
|
|
case 12 : sigval = 11; break; /* stack exception */
|
|
case 13 : sigval = 11; break; /* general protection */
|
|
case 14 : sigval = 11; break; /* page fault */
|
|
case 16 : sigval = 7; break; /* coprocessor error */
|
|
default:
|
|
sigval = 7; /* "software generated"*/
|
|
}
|
|
return (sigval);
|
|
}
|
|
|
|
/**********************************************/
|
|
/* WHILE WE FIND NICE HEX CHARS, BUILD AN INT */
|
|
/* RETURN NUMBER OF CHARS PROCESSED */
|
|
/**********************************************/
|
|
int hexToInt(char **ptr, int *intValue)
|
|
{
|
|
int numChars = 0;
|
|
int hexValue;
|
|
|
|
*intValue = 0;
|
|
|
|
while (**ptr)
|
|
{
|
|
hexValue = hex(**ptr);
|
|
if (hexValue >=0)
|
|
{
|
|
*intValue = (*intValue <<4) | hexValue;
|
|
numChars ++;
|
|
}
|
|
else
|
|
break;
|
|
|
|
(*ptr)++;
|
|
}
|
|
|
|
return (numChars);
|
|
}
|
|
|
|
/*
|
|
* This function does all command procesing for interfacing to gdb.
|
|
*/
|
|
void handle_exception(int exceptionVector)
|
|
{
|
|
int sigval;
|
|
int addr, length;
|
|
char * ptr;
|
|
int newPC;
|
|
|
|
gdb_i386vector = exceptionVector;
|
|
|
|
if (remote_debug) printf("vector=%d, sr=0x%x, pc=0x%x\n",
|
|
exceptionVector,
|
|
registers[ PS ],
|
|
registers[ PC ]);
|
|
|
|
/* reply to host that an exception has occurred */
|
|
sigval = computeSignal( exceptionVector );
|
|
remcomOutBuffer[0] = 'S';
|
|
remcomOutBuffer[1] = hexchars[sigval >> 4];
|
|
remcomOutBuffer[2] = hexchars[sigval % 16];
|
|
remcomOutBuffer[3] = 0;
|
|
|
|
putpacket(remcomOutBuffer);
|
|
|
|
while (1==1) {
|
|
error = 0;
|
|
remcomOutBuffer[0] = 0;
|
|
getpacket(remcomInBuffer);
|
|
switch (remcomInBuffer[0]) {
|
|
case '?' : remcomOutBuffer[0] = 'S';
|
|
remcomOutBuffer[1] = hexchars[sigval >> 4];
|
|
remcomOutBuffer[2] = hexchars[sigval % 16];
|
|
remcomOutBuffer[3] = 0;
|
|
break;
|
|
case 'd' : remote_debug = !(remote_debug); /* toggle debug flag */
|
|
break;
|
|
case 'g' : /* return the value of the CPU registers */
|
|
mem2hex((char*) registers, remcomOutBuffer, NUMREGBYTES, 0);
|
|
break;
|
|
case 'G' : /* set the value of the CPU registers - return OK */
|
|
hex2mem(&remcomInBuffer[1], (char*) registers, NUMREGBYTES, 0);
|
|
strcpy(remcomOutBuffer,"OK");
|
|
break;
|
|
|
|
/* mAA..AA,LLLL Read LLLL bytes at address AA..AA */
|
|
case 'm' :
|
|
/* TRY TO READ %x,%x. IF SUCCEED, SET PTR = 0 */
|
|
ptr = &remcomInBuffer[1];
|
|
if (hexToInt(&ptr,&addr))
|
|
if (*(ptr++) == ',')
|
|
if (hexToInt(&ptr,&length))
|
|
{
|
|
ptr = 0;
|
|
mem_err = 0;
|
|
mem2hex((char*) addr, remcomOutBuffer, length, 1);
|
|
if (mem_err) {
|
|
strcpy (remcomOutBuffer, "E03");
|
|
debug_error ("memory fault");
|
|
}
|
|
}
|
|
|
|
if (ptr)
|
|
{
|
|
strcpy(remcomOutBuffer,"E01");
|
|
debug_error("malformed read memory command: %s",remcomInBuffer);
|
|
}
|
|
break;
|
|
|
|
/* MAA..AA,LLLL: Write LLLL bytes at address AA.AA return OK */
|
|
case 'M' :
|
|
/* TRY TO READ '%x,%x:'. IF SUCCEED, SET PTR = 0 */
|
|
ptr = &remcomInBuffer[1];
|
|
if (hexToInt(&ptr,&addr))
|
|
if (*(ptr++) == ',')
|
|
if (hexToInt(&ptr,&length))
|
|
if (*(ptr++) == ':')
|
|
{
|
|
mem_err = 0;
|
|
hex2mem(ptr, (char*) addr, length, 1);
|
|
|
|
if (mem_err) {
|
|
strcpy (remcomOutBuffer, "E03");
|
|
debug_error ("memory fault");
|
|
} else {
|
|
strcpy(remcomOutBuffer,"OK");
|
|
}
|
|
|
|
ptr = 0;
|
|
}
|
|
if (ptr)
|
|
{
|
|
strcpy(remcomOutBuffer,"E02");
|
|
debug_error("malformed write memory command: %s",remcomInBuffer);
|
|
}
|
|
break;
|
|
|
|
/* cAA..AA Continue at address AA..AA(optional) */
|
|
/* sAA..AA Step one instruction from AA..AA(optional) */
|
|
case 'c' :
|
|
case 's' :
|
|
/* try to read optional parameter, pc unchanged if no parm */
|
|
ptr = &remcomInBuffer[1];
|
|
if (hexToInt(&ptr,&addr))
|
|
registers[ PC ] = addr;
|
|
|
|
newPC = registers[ PC];
|
|
|
|
/* clear the trace bit */
|
|
registers[ PS ] &= 0xfffffeff;
|
|
|
|
/* set the trace bit if we're stepping */
|
|
if (remcomInBuffer[0] == 's') registers[ PS ] |= 0x100;
|
|
|
|
/*
|
|
* If we found a match for the PC AND we are not returning
|
|
* as a result of a breakpoint (33),
|
|
* trace exception (9), nmi (31), jmp to
|
|
* the old exception handler as if this code never ran.
|
|
*/
|
|
#if 0
|
|
/* Don't really think we need this, except maybe for protection
|
|
exceptions. */
|
|
/*
|
|
* invoke the previous handler.
|
|
*/
|
|
if (oldExceptionHook)
|
|
(*oldExceptionHook) (frame->exceptionVector);
|
|
newPC = registers[ PC ]; /* pc may have changed */
|
|
#endif /* 0 */
|
|
|
|
_returnFromException(); /* this is a jump */
|
|
|
|
break;
|
|
|
|
/* kill the program */
|
|
case 'k' : /* do nothing */
|
|
#if 0
|
|
/* Huh? This doesn't look like "nothing".
|
|
m68k-stub.c and sparc-stub.c don't have it. */
|
|
BREAKPOINT();
|
|
#endif
|
|
break;
|
|
} /* switch */
|
|
|
|
/* reply to the request */
|
|
putpacket(remcomOutBuffer);
|
|
}
|
|
}
|
|
|
|
/* this function is used to set up exception handlers for tracing and
|
|
breakpoints */
|
|
void set_debug_traps()
|
|
{
|
|
extern void remcomHandler();
|
|
int exception;
|
|
|
|
stackPtr = &remcomStack[STACKSIZE/sizeof(int) - 1];
|
|
|
|
exceptionHandler (0, _catchException0);
|
|
exceptionHandler (1, _catchException1);
|
|
exceptionHandler (3, _catchException3);
|
|
exceptionHandler (4, _catchException4);
|
|
exceptionHandler (5, _catchException5);
|
|
exceptionHandler (6, _catchException6);
|
|
exceptionHandler (7, _catchException7);
|
|
exceptionHandler (8, _catchException8);
|
|
exceptionHandler (9, _catchException9);
|
|
exceptionHandler (10, _catchException10);
|
|
exceptionHandler (11, _catchException11);
|
|
exceptionHandler (12, _catchException12);
|
|
exceptionHandler (13, _catchException13);
|
|
exceptionHandler (14, _catchException14);
|
|
exceptionHandler (16, _catchException16);
|
|
|
|
if (exceptionHook != remcomHandler)
|
|
{
|
|
oldExceptionHook = exceptionHook;
|
|
exceptionHook = remcomHandler;
|
|
}
|
|
|
|
/* In case GDB is started before us, ack any packets (presumably
|
|
"$?#xx") sitting there. */
|
|
putDebugChar ('+');
|
|
|
|
initialized = 1;
|
|
|
|
}
|
|
|
|
/* This function will generate a breakpoint exception. It is used at the
|
|
beginning of a program to sync up with a debugger and can be used
|
|
otherwise as a quick means to stop program execution and "break" into
|
|
the debugger. */
|
|
|
|
void breakpoint()
|
|
{
|
|
if (initialized)
|
|
#if 0
|
|
handle_exception(3);
|
|
#else
|
|
BREAKPOINT();
|
|
#endif
|
|
waitabit();
|
|
}
|
|
|
|
int waitlimit = 1000000;
|
|
|
|
#if 0
|
|
void
|
|
bogon()
|
|
{
|
|
waitabit();
|
|
}
|
|
#endif
|
|
|
|
void
|
|
waitabit()
|
|
{
|
|
int i;
|
|
for (i = 0; i < waitlimit; i++) ;
|
|
}
|